Producing homogenous alloys of high temperature reactive metals such as titanium and zirconium has presented problems. U.S. Pat. No. 3,565,602 issued to Konisi et al on Feb. 23, 1971 discusses the problem of adding constituents with different melting points and several prior art methods of dealing with these problems. The greater the temperature difference of melting points the more difficult these problems become. Tin is commonly added as an alloying constituent of zirconium alloys and is an example of a low melting point constituent, the introduction of which presents significant difficulties. While alloying constituents are often added using master alloys, master alloys of zirconium and titanium have a tendency to be pyrophoric and are prone to contribute undesirable phases such as nitrides to the alloys. Further, the master alloy is still relatively low melting and resistance heating of the electrode tends to melt the master alloy away from the arc, resulting in an inhomogeneous product. To control the amount of tin during arc melting it is common practice to contain the unalloyed tin within a tight packet of some form within the electrode.
Attempts have also been made to reduce the electrode resistance to minimize resistance heating of the electrode during melting by, for example, providing multiple welding beads longitudinally along the electrode. This technique is time consuming and not totally effective.